This invention relates to a starting system for internal combustion engines. More particularly, it relates to an improved structure of a starter which is adapted to drive a second load device.
Heretofore, there has been a system of the pertinent type as shown in FIG. 1. Referring to the figure, numeral 1 designates a starter, and numeral 2 a pinion which is mounted on the rotary shaft 1a of the starter 1. The pinion 2 has a built-in overrunning clutch (not shown), and it is held in meshing engagement with a ring gear 5 which is fastened to the crankshaft 4 of an engine 3. Numeral 6 indicates a spur gear which is similarly engaged with the rotary shaft 1a through a one-way clutch (not shown) so as to afford a unidirectional turning force reversely to that of the pinion 2. A spur gear 8 which is fastened to the rotary shaft (crankshaft) of an air pump 7 being a second load device, is held in meshing engagement with the spur gear 6 and is urged to drive by the spur gear 6.
In operation, when the starter 1 is rotated in its forward direction, the pinion 2 is rotated through the overrunning clutch (not shown). The resulting turning force is transmitted to the ring gear 5, to rotate the crankshaft 4 and to start the engine 3. After the starting of the engine 3, the pinion 2 is reversely urged through the ring gear 5. Herein, a turning force from the engine 3 is not transmitted to the starter 1 due to the action of the overrunning clutch (not shown) built in the pinion 2, so that the starter 1 is not urged to over-rotate. Next, there will be described a case of driving the air pump 7 as required. When the drive direction of the starter 1 is reversed by a built-in reversing device (not shown), the spur gear 6 is rotated through the one-way clutch (not shown). The air pump 7 is rotated through the spur gear 8 held in meshing engagement with the spur gear 6, and it pumps air as required. At this time, the turning force of the starter 1 is prevented from being transmitted to the ring gear 5 of the engine 3, under the action of the overrunning clutch (not shown) built in the pinion 2.
The prior-art system is constructed as described above, and the pinion 2 and the ring gear 5 are normally held in meshing engagement with each other. This has led to the disadvantage that the system wears away quickly.